Autoimmune Pancreatitis

Autoimmune pancreatitis occurs when your immune system triggers swelling and inflammation in your pancreas. It happens when your body confuses healthy cells for germs and attacks them.

How common is autoimmune pancreatitis?

Autoimmune pancreatitis is rare, occurring in less than 1 in 100,000 people. It accounts for only 2% of all cases of long-lasting (chronic) pancreatitis.

Are there different types of autoimmune pancreatitis?

There are two types of autoimmune pancreatitis:

Type 1 autoimmune pancreatitis is more common. It’s associated with high levels of a protein called immunoglobulin G4 (IgG4). High levels of IgG4 antibodies occur when there’s inflammation. IgG4 protein is an antibody that produces immune cells.

Type 1 doesn’t only affects your pancreas. It can cause inflammation and damage in other organs, including your:

• Bile ducts (tiny tubes that transport bile from your liver to your small intestine).
• Kidney ducts (renal tubes).
• Liver.
• Lungs.
• Gallbladder.
• Salivary glands.
• Thyroid.

Type 2 autoimmune pancreatitis only affects your pancreas. It occurs when white blood cells called neutrophils damage your pancreas and pancreas ducts. People with this condition are often younger and have inflammatory bowel disease.